Aperture tube assembly

ABSTRACT

An assembly which includes a plurality of particle counting and sizing aperture tubes for use with a particle analyzer of the Coulter Type, the tubes being mounted on a turret structure to enable any chosen one to be used in the system to the exclusion of the others, the tubes being readily removed or replaced without affecting or requiring disassembly of the remainder of the apparatus.

United States Patent 1 1 3,763,429 Hoskins Oct. 2, 1973 APERTURE TUBE ASSEMBLY 3,444,464 5/1969 Coulter et al 324/71 CP [75] Inventor: Douglas H. Hoskins, St. Albans,

Hertfordshire England Primary Examiner-Alfred E. Smith [73] Assignee: Coulter Electronics, Inc., Hialeah, Attorney-l Irving Silverman et Fla.

[22] Filed: Apr. 12, 1972 [57] ABSTRACT [21] Appl. N0.: 243,269

An assembly which includes a plurality of particle counting and sizing aperture tubes for use with a partii 1 :1 cle analyzer of the Coulter Type, the tubes being [58] Field of search-W IIIIIIII 324/71 mounted on a turret structure to enable any chosen one to be used in the system to the exclusion of the others,

356/208 the tubes being readily removed or replaced without t' f t d f [56] References Cited atfl'teggggrzrugequmng dlsassembly 0 he remain er 0 UNITED STATES PATENTS 1,969,08! 8/1934 Vogel-Jorgensen 73/425.6 4 Claims, 2 Drawing Figures 70 g0400 a 57 V Z 5? j 4;

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will! "m II rai APERTURE TUBE ASSEMBLY CROSS-REFERENCE TO RELATED APPLICATION The invention herein is an improvement over structure disclosed in a copending patent application Ser. No. 173,988, filed Aug. 23, 1971, in the name of Walter R. Hogg and entitled Aperture Tube Assembly for a Particle Study Apparatus owned by the assignee of the application herein.

BACKGROUND OF THE INVENTION The copending application disclosed a structure which included a plurality of aperture tubes integral with a rotating turret piece that could be rotated to connect any one of the aperture tubes into the liquid system of Coulter particle analyzing apparatus to the exclusion of all other aperture tubes. In this way, there could be several tubes having different size apertures available for different kinds of tests. The glassware was expensive and difficult to manufacture and once assembled was limited in use to the size of apertures contained in the aperture tubes. Breakage of any tube would put the entire structure out of use until the single tube could be repaired, and such repair required handling the entire structure, removing the broken tube by cutting, then replacing it by fusing, etc.

The invention obviates the problems as set forth above.

Reference may be had to U.S. Pat. Nos. 2,656,508, 2,985,830, 3,389,334, 3,444,463 and 3,444,464 for disclosure of Coulter apparatus involved and showing the state of the art.

SUMMARY OF THE INVENTION The invention is characterized by the provision of aperture tubes which are readily removable from the turret piece, being telescopically held in place by ground glass joints. In this manner conventional aperture tubes may be used. These are readily changed, replaced, etc. giving the user a wide choice of apertures, and not requiring the disassembly of the structure when an aperture tube is changed.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary sectional view showing a turret structure constructed in accordance with the invention, one of the aperture tubes being immersed in a beaker of electrolyte having particles suspended therein and FIG. 2 is a diagrammatic top plan view showing an aperture tube assembly constructed in accordance with the invention aligned with a viewing system.

DESCRIPTION OF THE PREFERRED EMBODIMENT The aperture tube assembly 16 is secured to a hollow housing 30 of circular cross section having a closed end 34, its upper end connected to a control piece (not shown) and having a single lateral port 35 in its side wall. The electrode 28 is disposed close to the port 35. At the bottom of the housing is an integral depending post 36 which serves as a mounting device for holding the aperture tube assembly 16 connected to the control piece with the cooperation of an annular cap 38, a compression spring 40, a washer 42 and a cotter pin 44. The housing is tapered toward themounting post and the connection is ground to provide an accurate easily rotating and fluid tight engagement between the assembly 16 and the housing 30.

The aperture tube assembly 16 includes a generally cylindrical female turret piece or fitting 50 having a plurality of integral, generally downwardly slanting radiating branches such as 52 and 54 terminating at 53 and 55 respectively in downwardly opening, tapered, ground glass male spigots. The turret piece 50 is designed to be rotated to align the port 35 with any chosen one of the branches 52 or 54. Each spigot 53 and 54 has an aperture tube telescopically engaged thereon in fluid tight connection, such tubes being shown at 46 and 48, respectively, being held in place by means of extensible springs 47 and 49 engaging between suitable hooks 51 integrally formed on the aperture tubes and the spigots as shown. These aperture tubes 46 and 48 may be commercially available aperture tubes used, for example, in commercial apparatus known as the Coulter Counter constructed in accordance with U.S. Pat. No. 2,656,508. The construction of the tubes themselves may be in accordance with U.S. Pat. No. 2,985,830.

The lower end of each aperture tube 46 and 48 is provided with a scanning aperture such as the one shown at 58 through which a suspension of particles in electrolyte may be drawn for the counting and/or sizing of the particles. The apertures may be of different size, and it will be obvious that it is a simple matter to exchange aperture tubes to use any size of aperture desired without fully disassembling the apparatus. Also breakage of an aperture tube is no problem since it is easily replaced without disturbing the remainder of the glassware.

As shown, the chosen aperture tube such as 48 is immersed in a beaker 66 of suspension and an electrode 68 extends to the detecting apparatus by way of the lead 70. The other electrode 28 is also connected to a lead 31 which extends to the detector. The interior of the glassware is filled by means of connections 76 and 78 functioning with the extension tubes 77 and 79 that extend to the bottom of the aperture tubes by the flexible connectingplastic pipes 81. The liquid on the interior is electrolyte and provides a conductive path between electrodes, or if desired, there can be extension electrodes in the upper bores of the branches 52 and 54 connected with electrodes extending down to the bottoms of the aperture tubes 46 and 48.

Although only two aperture tubes are shown there can be an assembly of three on the turret piece 50. FIG. 2 shows how such an arrangement is used. Any one of the three aperture tubes 46, 48 or 96 may be rotated into position where it can be immersed in the beaker 66 and then will be in alignment with the beam from the lamp 98 and suitable optical apparatus (not shown) to be projected in the objective lens 94 of a microscope, projector or the like so that the image of the aperture can be viewed.

What it is desired to secure by Letters Patent of the United States is:

I. An aperture tube assembly for use with an electronic particle study apparatus of the Coulter type, comprising A. a turret-like hollow fitting having a lateral wall of generally cylindrical interior configuration and having a plurality of hollow integral connecting branches radiating outwardly from said fitting and all opening through said wall at the points where they are respectively connected to said wall,

B. each branch having a depending spigot and each spigot adapted to receive an aperture tube thereon in telescopic, fluid-tight, removable relationship and C. a central housing having a lateral wall whose exterior configuration is cylindrical and in mating engagement with the interior configuration of the hollow fitting in rotatable fluid-tight connection,

i. said central housing having a single port in its lateral wall located with respect to the openings of the respective branches such that when said port is aligned with one opening all of the remaining openings are blocked by the imperforate portion of said lateral wall of said central housing.

2. The apparatus as claimed in claim 1 which includes an aperture tube removably secured to each spigot.

3. The apparatus as claimed in claim 2 in which there is an electrode disposed on the interior of said central housing in order to make elctrical communication through liquid carried in said housing, the branch aligned with said port and the aperture tube mounted on said branch.

4. The apparatus as claimed in claim 2 in which each spigot has a male conical tapered configuration and each aperture tube has a conforming conical tapered entrance. 

1. An aperture tube assembly for use with an electronic particle study apparatus of the Coulter type, comprising A. a turret-like hollow fitting having a lateral wall of generally cylindrical interior configuration and having a plurality of hollow integral connecting branches radiating outwardly from said fitting and all opening through said wall at the points where they are respectively connected to said wall, B. each branch having a depending spigot and each spigot adapted to receive an aperture tube thereon in telescopic, fluid-tight, removable relationship and C. a central housing having a lateral wall whose exterior configuration is cylindrical and in mating engagement with the interior configuration of the hollow fitting in rotatable fluid-tight connection, i. said central housing having a single port in its lateral wall located with respect to the openings of the respective branches such that when said port is aligned with one opening all of the remaining openings are blocked by the imperforate portion of said lateral wall of said central housing.
 2. The apparatus as claimed in claim 1 which includes an aperture tube removably secured to each spigot.
 3. The apparatus as claimed in claim 2 in which there is an electrode disposed on the interior of said central housing in order to make elctrical communication through liquid carried in said housing, the branch aligned with said port and the aperture tube mounted on said branch.
 4. The apparatus as claimed in claim 2 in which each spigot has a male conical tapered configuration and each aperture tube has a conforming conical tapered entrance. 